The study is designed as a randomised controlled 2 x 4 weeks cross-over trial, initiated with a 1-week run-in period. The study sample will consist of 60 volunteer physicians, nurses and nursing assistants from Herlev University Hospital in Copenhagen, Denmark. A healthy lunch and snack meal meeting the current danish diet recommendations will be delivered daily during all working days in the intervention period. During the control period, the participants are requested to maintain their habitual dietary intake at work. Reaction time will be assessed by reaction time test Go/No-Go, a subtest of Test-battery for Attention Performance. Changes in mood will be measured by the Profile of Mood State questionnaire. In addition, dietary intake, level of physical activity and palatability of the intervention diet will be registered.